Behaviorism is closely associated with S-R psychology. According to one interpretation of S-R, the S-R reflex thesis, all behavior can be analyzed into discrete stereotyped movements, each of which is elicited by an immediately preceding discrete impinging of energy on a sensory receptor.
No important behaviorist theories actually conform to this simple reflexological model. Typically they include principles of learning, internal stimuli, integration, and coordination, which violate the conditions of the model. The inclusion of mediation, especially the habit-family hierarchy, in many behaviorist theories further undermines the model.
All that remains of the original S-R reflex thesis is the assertion that behavior consists of responses, each caused by antecedent stimuli. Even this weakened version of the thesis is contradicted by the concept of the operant, which is emitted rather than elicited. An even weaker version is: All behavior is functionally related to environmental independent variables. Interbehaviorists object to this version and argue that behavior and the environment reciprocally determine one another.
According to a second interpretation of S-R, the S-R learning thesis, learning consists of the association of stimuli and responses. This contrasts with S-S theories, which assert that learning is the acquisition of knowledge. A major problem with S-S theories is in bridging the gap between knowledge and behavior. Often this is accomplished by intuition rather than objective deduction. In S-R theories it is accomplished by including a response term in the primitive learning operation.
The claim that the S-R learning thesis is "narrow" ignores the complexity of major S-R learning theories and functional definition. A second objection to the S-R learning thesis is that learning can occur without a response. In reply, S-R theorists try to show that such learning is derivable from learning operations that do involve a response.
Given the behaviorist philosophy explicated in part I, a science of behavior can develop in many ways as substantive content fills the conceptual frame-